Matrix for stereotype-plate molds.



A. EGLI. MATRIX FOR STEREOTYPE PLATE MOLDS.

APRLIGATION FILED NOV. 10; 1909.

1,026,739. Patented May 21, 1912.

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COLUMBIA PLANDGRAPH co.. WASHINGTON, I) c.

UNITED STATES PATENT OFFICE.

ARNOLD EGLI, 0F PLAUEN, GERMANY, ASSIGNOR TO VOGTIANDISGHE- MASCHINEN- FABRIK (VORMALS J. C. & H. DIETRICI-I) ACTIENG-ESELLSCHAFT, 0F PLAUEN, GER- MANY.

MATRIX FOR STEREOTYPE-PLATE MOLDS.

To all whom it may concern:

Be it known that I, ARNOLD EGLI, a sub ject of the King of- Prussia, residing at Plauen, in Vogtlande, in the Kingdom of Saxony and German Empire, have invented new and useful Improvements in Matrices for Stereotype-Plate Molds, of which the following is a specification.-

The subject of my invention is a matrix for the molds employed in casting stereotype-plates. 7

According to my invention the matrix presents not only the usual marginal elevation for damming or restraining the liquid metal, but is also provided along its top edge (which during the casting process is located directly at the gate, or place where the molten metal is run in) with one or more additional elevations or protruding portions of any suitable shape. The purpose of these auxiliary protrusions is to accommodate the depressions due to shrinkage which-depressions occur on the setting or solidifying of the plate. The elevation ordinarily provided around the edge of the matrix for the purpose of restraining the molten metal exerts no influence upon the depressions occurring on the setting of the cast plate, since said elevation is located too close to the text. It is only the marginal elevations, located beyond the said elevation which confines the printing-surface of the plate, that are able to accommodate the requisite quantity of still uncongealed feeder-metal for supplying the depressions,

A practical embodiment of my invention is illustrated in the accompanying drawing, in which Figure 1 is a plan of the matrix, and Fig. 2 a section on the line AA of Fig. 1. Fig. 3 is a sectional view, showing the matrix in the mold.

The matrix 6 which is placed in the mold c, a) for the stereotype-plate, consists of stoutpaper, having the composition stamped or Specification of Letters Patent.

Application filed November 10, 1909.

Patented May 21, 1912. Serial No. 527,235.

pressed into it, and provided with the usual marginal rib or protrusion a, adapted to confine the text or impressed composition. This rib, or elevation (L, however, acts solely to dam or restrain the molten metal in the casting operation. For,despite the elevation, it frequently occurs in casting that on the setting of the cast plate, the depressions due to shrinkage form directly in the elevation a and even in the printing-surface, that is, the text of the plate, whereby the cast stereotype-plate is rendered of course useless. According to my invention the depressions which occur on the setting of the plate are caused to form with certainty entirely outside of the actual printing-surface. This effect is obtained by the matrix being furnished beyond the usual elevation which confines the text, or printingsurface, with other raised parts or protrusions I), along its top edge, 2'. e., at the place where the metal is poured in. These supplementary elevations accommodate the depressions. They may be of course of any suitable shape and may be if desired connected with each other at certain places by cross members.

When the hot metal is poured into the mold c, d, at f in Fig. 3, part of the metal will run into the grooves formed by the elevations a, b. As the plate begins to shrink, liquid metal will be sucked away at a (Fig. 8). The depression caused thereby is, however, filled up again with the hot liquid metal that has been dammed up by the elevation b. The matrix 6 being made of paper, which is a poor conductor of heat, the hot metal around the elevations will keep liquid a longer time than the metal forming the plate, hence there is always a suflicient quantity of liquid metal to fill the depressions occurring through shrinkage, while the plate solidifies.

The advantage of my invention lies in the fact that at the first casting operation, always a perfect printing surface is obtained, since every operation is successful. ated beyond said elevation and adapted to The process of casting stereotype plates is accommodate any depressions due to shrinkthereby, of course, greatly expedited. age of the metal within said elevation.

Having thus described my invention, I In testimony whereof I have signed my 5 declare that What I claim as new and desire name to this specification in the presence of 15 to secure by Letters Patent is two subscribing witnesses.

A matrix for molds for casting stereo- ARNOLD EGLI. type-plates, provided with the usual eleva- Witnesses: tion for restraining the liquid metal and a ERNST WAGNER, 10 number of supplementary elevations, situ- ROBERT HEINRICH NIER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

